Lee, a two-time All-Star left fielder who played with Texas and Milwaukee last season, signed a six-year, $100 million deal, the largest contract in Astros history. Last season was Lee's fifth straight with at least 30 home runs and 99 RBI.

"This is a historic commitment to winning," Astros general manager Tim Purpura said.

According to MLB.com, the deal will pay Lee $11 million in 2007 (plus a $3 million signing bonus), $12 million in 2008, and $18.5 million for each of the last four seasons. The contract runs through the 2012 season.

A source told ESPN.com's Jayson Stark the only significant non-monetary clause in the contract is that Lee will have a complete no-trade clause for the first four years of the deal and a limited no-trade for the final two years.

"I know this is a team where I have a good chance to win a championship. I've always liked this team, they're always very good, and I like this ballpark. I like a lot about Houston. That's why I told my agent this was one of the places I'd like to play."

Adding Lee will give the Astros another power threat besides All-Star first baseman Lance Berkman, who had 45 home runs and 136 RBI and finished third in NL MVP voting behind Philadelphia's Ryan Howard and St. Louis' Albert Pujols.

Astros manager Phil Garner, who said Houston will be a better team with Lee in the heart of the order, said the deals show Houston owner Drayton McLane Jr. is "stepping up in a big way."

"We feel like these are two big questions that have been answered for us," Garner said. "Carlos will fit very nicely in the middle of that lineup -- oh, my goodness, that's going to be nice. I'm sure that Berkman is over there enjoying his turkey dinner a lot better right now, knowing there's just no way now they're going to get around him. By adding these two guys we'll be definitely better."

Houston was last in the NL in batting average at .255 and languished out of the pennant race until a late-season run that almost overtook World Series champion St. Louis.

"I remember watching Carlos with the White Sox and with the Brewers and he broke our hearts a few times," McLane, quoted by MLB.com, said. "His statistics are as good as they get. Woody has broken our hearts a few times, too, and we're glad to have him. This is by far the biggest single commitment in the history of the Houston Astros."

Lee hit 28 homers in 102 games for the Brewers before the Rangers picked him up a few days before the July trade deadline. His power numbers dipped after that, but he finished with combined totals of 37 home runs and 116 RBI. He hit .300, including .322 in 59 games with the Rangers.

Williams, who grew up in Houston and was a college star there, is a 14-year veteran who was 12-5 with a 3.65 ERA last season with San Diego, his best ERA since 2002 with St. Louis. He signed a two-year deal worth $12.5 million, with a club option for a third year worth another $6.5 million.

"I've been waiting to do this for a long time," said Williams, who grew up an Astros fan. "I always dreamed of putting this uniform on."

Williams, 40, is 124-101 with a 4.09 ERA in 391 career games, including 299 starts. Purpura said Williams could be a steadying veteran influence on the club's younger pitchers.

The Astros' staff is anchored by right-hander Roy Oswalt, who signed a five-year, $73 million contract in August. Both Clemens and Pettitte are free agents and haven't said whether or where they want to play next year.

Lee's signing Friday was the third major free-agent loss for the Rangers in the last two weeks. Mark DeRosa, a valuable starter at several positions, signed with the Chicago Cubs, and All-Star center fielder Gary Matthews Jr. signed a five-year, $50 million deal with the Los Angeles Angels this week.

Information from The Associated Press and MLB.com was used in this report.